The use of cathodic deposition as an electrolytic technique for the extraction of a metal from a solution which, because it is conductive can be termed an electrolyte, has long been known. The technique is currently used to recover precious metals which are in solution in an ionic form for the decontamination of effluents polluted with heavy metals such as cadmium, nickel, copper and mercury and for various analytic purposes.
The known techniques require specially designed electrolysis cells which, because of their cost, frequently cannot be used in a practical manner for the recovery of small quantities of metals.